Spontaneous uterine rupture due to adenomyosis in a nongravid,nulliparous woman: A case report

Abstract

Spontaneous uterine rupture outside of pregnancy is exceptionally rare, with adenomyosis potentially acting as a structurally weakening substrate. Most reports involve gravid patients, underscoring the unusual nature of nongravid presentations. We report the case of a 26-year-old nongravid, nulliparous woman who presented with sudden, diffuse abdominal pain and hemorrhagic shock. Imaging revealed a markedly enlarged, heterogeneous uterus with hemoperitoneum. Emergency laparotomy evacuated approximately 3000 mL of blood. Multiple transmural ruptures precluded repair, necessitating total hysterectomy with adnexal preservation. Histopathology confirmed diffuse adenomyosis with extensive hemorrhagic necrosis.

This case highlights that in reproductive-age women presenting with an acute abdomen, a negative pregnancy test, and an enlarged heterogeneous uterus, spontaneous rupture secondary to adenomyosis should be considered. Early resuscitation and definitive surgical management are critical, and proactive counseling is recommended for patients with severe adenomyosis who may be at risk for catastrophic decompensation.

Introduction

Uterine rupture is a severe, life-threatening condition that most commonly occurs during pregnancy and is typically associated with risk factors such as prior cesarean section scars, uterine malformations, and trauma.^1–3 Spontaneous rupture of the nongravid uterus is extremely rare, with adenomyosis being an even less common underlying cause. Adenomyosis is a benign gynecological disorder characterized by the presence of endometrial glands and stroma within the myometrium.^4,5 Although adenomyosis has been occasionally linked to spontaneous uterine rupture, its occurrence in nongravid women is exceedingly rare.^6,7 This report aimed to raise awareness among clinicians regarding this rare but potentially life-threatening complication.

Case presentation

This study was conducted in accordance with the ethical principles outlined in the Declaration of Helsinki and was approved from the Ethics Committee of Ya’an People’s Hospital (Approval Number: 7622413). The reporting of this study conforms to the Case Report (CARE) guidelines. ⁸ A 26-year-old unmarried, nulligravid woman was transferred to the emergency department in a faint state. Her family reported that she had experienced severe abdominal pain for more than 24 h. The pain had initially begun as mild lower abdominal discomfort 1 week earlier, progressively worsening until it became diffuse, unbearable, and accompanied by syncope on the day before admission. She had self-administered analgesics; however, her symptoms did not improve.

She was initially evaluated at a local county hospital, where computed tomography (CT) revealed a markedly enlarged uterus measuring 16.2 × 10.0 cm² with heterogeneous density and diffusely distributed patchy low-density areas, findings suggestive of adenomyosis (Figure 1(a)). A large volume of peritoneal fluid with low-density clusters indicated intra-abdominal hemorrhage (Figure 1(b)). Laboratory test findings demonstrated a white blood cell count of 25.74 × 10⁹/L, neutrophil percentage of 91.1%, and hemoglobin level of 83 g/L. Coagulation tests findings showed a prolonged prothrombin time of 19.2 s and a fibrinogen level of 0.44 g/L.

Figure 1.

CT images of the abdomen and pelvic cavity. (a) CT revealed a markedly enlarged uterus measuring 16.2 × 10.0 cm² with heterogeneous density and diffusely distributed patchy low-density areas, findings suggestive of adenomyosis and (b) a large volume of peritoneal fluid with low-density clusters indicated intra-abdominal hemorrhage. CT: computed tomography.

Due to her critical condition, she was transferred to Ya’an People’s Hospital, Ya’an City, Sichuan Province, China, in July 2025. On arrival, her blood pressure was 70/40 mmHg, and her heart rate was 168 beats/min. She appeared pale and drowsy but remained responsive. These findings were consistent with hemorrhagic shock. The working diagnosis included hemorrhagic shock, intra-abdominal hemorrhage, and coagulation dysfunction. After obtaining written informed consent for treatment and publication, she was urgently transferred to the operating room with rapid fluid resuscitation.

Intraoperatively, approximately 3000 mL of blood clots and dark red blood were found in the abdominal and pelvic cavities. The uterus was uniformly enlarged to the size of a 5-month gestation and exhibited a purple–blue, spherical appearance (Figure 2). It was soft and bag-like, showing extensive necrosis and occupying the entire pelvic cavity (Figure 2). Multiple rupture sites were observed at the uterine cornua and the right posterior uterine wall. Large amounts of dark red blood and friable, fish meat–like endometrial tissue extruded from these sites (Figure 2). The largest rupture, located at the left uterine cornua, measured approximately 3 × 4 cm² (Figure 2).

Figure 2.

Intraoperative observation of the uterus. The uterus was uniformly enlarged to the size of a 5-month gestation and exhibited purple–blue, spherical appearance. It was soft and bag-like, showing extensive necrosis and occupying the entire pelvic cavity. Multiple rupture sites were observed at the uterine cornua and the right posterior uterine wall. Large amounts of dark red blood and friable, fish meat–like endometrial tissue extruded from these sites.

Considering the patient’s age and her nulligravid and nulliparous status, uterine preservation was initially attempted. Vaginal curettage was performed to evacuate endometrial tissue to achieve hemostasis and reduce uterine volume. However, this approach failed due to massive hemorrhagic necrosis of the myometrium. After a detailed discussion with her family, a total hysterectomy with bilateral salpingectomy was performed, with both ovaries preserved.

Postoperative pathology revealed a uterus measuring 12 × 11 × 7 cm³ with diffuse adenomyosis and extensive hemorrhagic necrosis of the myometrium (Figure 3(a) and (b)). Ruptures were confirmed at the cornua and the adjacent uterine wall. The endometrium exhibited irregular hyperplasia with diffuse stromal hemorrhage, and the cervix showed chronic cervicitis with endometriosis.

Figure 3.

Pathological observation of the uterus. (a) Postoperative pathology revealed a uterus measuring 12 × 11 × 7 cm³ with and (b) diffuse adenomyosis and extensive hemorrhagic necrosis of the myometrium.

Discussion

Spontaneous rupture of the nongravid uterus is exceedingly rare and adenomyosis as the sole precipitating factor is even more uncommon. Most reported uterine ruptures occur during pregnancy and are associated with uterine scarring, abnormal placentation, or intrapartum trauma.^1–3,9 In contrast, rupture of an unscarred uterus is sporadic and, when described, typically occurs during gestation rather than in the nongravid state. Recent case-based reviews have identified adenomyosis as a potential pathologic substrate for rupture in otherwise unscarred uteri; however, most of these reports involve gravid patients.^6,10 Our case adds to the very limited literature documenting rupture in nongravid women with adenomyosis, including isolated reports in which sometimes patients had coexisting fibroids and presented with massive hemoperitoneum and shock.

Several pathophysiologic mechanisms may explain why adenomyosis predisposes the uterus to wall failure. Ectopic endometrial glands and stroma within the myometrium remodel the extracellular matrix and disrupt myometrial fiber continuity. Matrix metalloproteinase activity, aberrant angiogenesis, and receptor-mediated imbalances between proliferation and apoptosis have been implicated in weakening the myometrium.^11,12 Superimposed ischemia and focal hemorrhagic necrosis may further reduce its tensile strength, creating vulnerable zones that can rupture with modest increases in intrauterine pressure. These mechanisms are consistent with our intraoperative and histopathologic findings of diffuse adenomyosis with extensive hemorrhagic necrosis and multiple transmural rents.

Preoperative diagnosis is challenging. The clinical manifestations include sudden severe abdominal pain, hemoperitoneum, leukocytosis, and coagulopathy, which overlap with the symptoms of ruptured ovarian cyst, ruptured ectopic pregnancy, and acute peritonitis. In addition, ultrasonography and contrast-enhanced CT may reveal an enlarged, heterogeneous uterus with free intraperitoneal fluid and, occasionally, a focal defect in the uterine contour. In gravid patients with suspected adenomyosis, risk stratification aligned with the Morphological Uterus Sonographic Assessment (MUSA) framework has been recommended; however, its utility in the acute nongravid setting is limited by hemodynamic instability. ¹³ Nonetheless, our case and prior nongravid reports underscore that cross-sectional imaging can heighten suspicion and expedite surgical decision-making when a pregnancy test is negative but hemorrhagic shock is present. ¹⁴

Management priorities include rapid resuscitation, correction of coagulopathy, and timely surgical control of hemorrhage. ¹⁵ The operative strategy must balance life-saving hemostasis with fertility preservation whenever feasible. In gravid patients experiencing adenomyosis-related uterine rupture, reported surgical options range from uterine repair to hysterectomy, depending on the extent of damage and friability of the myometrium. Conservative repair may be possible for focal lacerations, whereas diffuse necrosis or multiple rupture sites often necessitate hysterectomy. ¹⁰ A similar spectrum applies to nongravid cases. In our patient, extensive transmural necrosis and multiple ruptures precluded repair, and hysterectomy with adnexal preservation was performed.

From a differential-diagnostic standpoint, clinicians should remain vigilant for atypical presentations. Nongravid adolescents and young adults have been reported to experience catastrophic hemorrhage resulting from rupture of adenomyosis or uterine leiomyoma, which can occasionally mimic uterine malignancy on imaging.^16,17 Recognizing that adenomyosis and uterine leiomyoma can present with acute uterine wall failure, even in the absence of pregnancy or prior uterine surgery, is crucial for preventing delays in definitive hemorrhage control.

This case offers several practical clinical guidelines. First, in women of reproductive age with known or suspected adenomyosis who present with abrupt abdominal pain, syncope, and imaging evidence of hemoperitoneum, spontaneous uterine rupture should be considered in the differential diagnosis after intrauterine and ectopic pregnancy have been excluded. Second, early activation of a massive transfusion protocol and expedited laparotomy are crucial, as delaying intervention while awaiting exhaustive imaging carries the risk of irreversible shock. Third, preoperative counseling of patients or family members should address the possibility of requiring a hysterectomy in case of diffuse myometrial necrosis, particularly in nulliparous patients, with emphasis on adnexal preservation to maintain hormonal function. Finally, for women with severe bulky adenomyosis and recurrent pain or anemia, proactive longitudinal management, including medical therapy, interventional options, or interval surgery, may reduce the risk of catastrophic presentations. However, evidence for rupture prevention remains anecdotal. Although this case report provides important clinical information for medical practitioners, the current findings may not be generalized to other patients.

Conclusion

Spontaneous uterine rupture attributable to adenomyosis can occur in nonpregnant, nulliparous women and should be considered in reproductive-age patients presenting with sudden abdominal pain, hemoperitoneum, and a negative pregnancy test. Cross-sectional imaging may raise suspicion; however, the diagnosis is often confirmed intraoperatively. Management requires immediate hemodynamic resuscitation followed by urgent surgical intervention. Repair might be feasible for focal defects, whereas diffuse myometrial necrosis commonly necessitates hysterectomy, with ovarian preservation considered when appropriate.